Hamann is convinced Liverpool are now preparing to axe their Dutch manager.
Liverpool go to West Ham tomorrow having lost nine of their past 12 games.
"Slot's end is near," Hamann told Sky Sport Germany. "I never thought it would come to this after the brilliant season he had, but I believe his credit has now run out.
"I believe Arne Slot has lost control of the team. It's falling apart, everyone is doing what they want, like (Mohamed) Salah before PSV's second goal.
"Liverpool will have major problems finishing in the Premier League top four. I don't believe these problems can be solved quickly or easily.
"The situation is so complex that the club will certainly be discussing the manager's position.
"If you ask the fans, many will surely say: 'That would be something'.
"How likely is it that he'll return to Liverpool? I have no idea. But it would be the story of the decade.
"The club will already have considered alternative managers. I assume they've spoken with Klopp."